# 1. ** a与b定义如下，下列哪个是正确的？ **
# a = '123
# ```
# b = '123'
# A.a != b
# B.a is b
# C.a == 123
# D.a + b == 246
# ```

a = '123'
b = '123'
print(a != b)  #False
print(a is b)   #True
print(a == 123)  #False
print(a + b == 246)  #False
